Snap switch



Jul! 2 1931- P. G. SHAW Q 1,816,749

SNAP SWITCH Fil'ed Sept. 3, 1930 I Inventor-z Per-cg G. Shaw,

His Attorney,

Patented July 28, 1931 UNITED? STATE 5' mama FATE Erica;

PERCY e. snaw, or BRIDGEPORT, CONNECTICUT, -AS.S.IGNQR-TO srnunanmucraru COMPANY, ACOBPORATIOII OF N-EWYOR-K i SNAP SWITCH Application filed September 3, .1930! Serial No. 479,442;

The present invention relates to small snap switches such as. are. used for controllingthe circuitgof electric. lamps and other small elecv trical devices. v

sion ofan improvedform of switch whichs. simple, in construction, of small dimensions, reliablei-n operation, and of lowm,anufactur;-- ing cost.-, 9 a For a'considerationof what I believe t -be novel and my invention, .attention is directed to. theyaccompanyingdescription: and the claims appendedithereto.

In thetaccompanyingdrawings which is D illustrativeofmy invention,Fig., '1 isa ,viewof a switch partly in .section v and partlyin elevation with the contacts incircuit closing relation; 'FigQZ-is a similarwview with the parts in open,.-circuit relation; Fig. 3 .is. a '20 perspective View .of the-actuator; F ig..4 'is;

a. perspective :view of the contact carrying.

member; Fig. -5 :is a tperspectizve'viewof, the. supportingiframe and.Fig. 6 is: a perspec; tive viewlofone of the movableucontactsi 6 indicates a base which is made-of porcelain,.or other. suitable insulating material, and 7 a cover for;:the=-.switch.parts1which-is; also lmadeof. insulating material, wherebyx danger of shocks to the useris avoided. The,

two pillars 9 forsupporting the cover 7from 36 its under side. The central partofthe. base is provided with a cavity orrecess10 through which the lower end of a contact carrying member moves-. Thebase is alsoprovided withia pair of aligned surfaces or shoulders? 11- upon which a supporting frame for the. switch parts is mounted'and held in place by:

screws 12. The frame is :UP-shaped iandiis. made. of one piece of thin sheet anetalbent to .shapeas best shown-in Fig. 5; It. iscpro vided .With base portions or feet -13 which restflort, the shoulders :11 of theoinsulatingi The object of-the invention isthe ;pr 'ovi-' base is oflciroular form and .isprovided-with. openings 8 toreceive screws: for attaching; the base to a suitablessuportn Formedin z tegraliwith the base-andrising above it,.ar,ef

actuator. Each side member ofthe frame. has two inclined or diverging walls 17,. and the junction or apex of thesefwallsformsa seat- 18 forthe pivotof the contact carrying member, the seats thusformed being directlybelowthe pivot 16 Iof theactuaton. The frameis also-providedvwith two downward 1y inclined walls 19 on?:each'side'which act asstops to limit the movement ofsthe contact carrying. member.. The walls 17Ifalsouact as stops'asshownin Fig.1." I 1 Referring now to Fig. 3, which shows the. actuator, this comprises a thin 'sheet metal member havinga head 20 that enclosed atall'points abovetheco'ver 7 by insulation 21,.which latter ismoulded'around the head in any suitable manner. The total thick nessof the insulation 2l is such that it fills; the space between the frame portions=15.,and is: prevented therebyfrom moving siclewiser, Formed integral-with theheadQO is a curved and downwardly extending arm 22 which terminates in a hook 23. This hook serves a doublefunction in that it forms an; attaching means-forthe lower end of the sprin'g24; Fig. 1, and also as'a stop. In Fig. 1 it will b'e seen that the hook isin contact-with the left-' handfoot 13 of the frame and' in Fig. 2 it is sho-wn'in contact with the right-'handffoot' 13 0f the framel- Fromlthis' it will appear so that the hook'limits the movements of'the' actuatorin-both directions. a Referring to Fig. 4 which;illustratesthecontact carrying m'embcr,-25 indicatesa sheet metal member which has large] central opening through which a part of the U- shaped frame extends: Ithas top bottomg and side walls and a pair of internal shoul-'= ders 26 which formed on the inner edges, of the side walls rest on the seats 18 when the actuator swings "from one of its positions to. the other.- The upper or topw'a'll has an opening-27 to receive the upper, end of thecoiled tension spring 24 Themember is causedto move with asnap action each time the axis i ofthe spring 24 vcrosses a vertical; plane assiiig through the. ivotal seats On account o h work l hasa cndo, theeactuatcr meta... silsuhst-sntia-l cause the frame extends through the opening 7 in the member 25 with small lateral clearthat the meeting surfaces .in v Fig. 1.,

fact, that it could not be bent or shaped to form contacts without danger of cracking the metal at each bend or corner. To obviate this difficulty, the member 25 is provided with two shoulders 28 on its lower side, and to each shoulder is secured a thin contact 29 which may be made of phosphor bronze or equivalent resilient material. To prevent the sides of the member 25 from spreading and also to hold the contacts in proper align-' ment, said sides are connected by the part 25". The contacts 29 may be secured to the actuatin member in any suitable manner, as by a tei ion 30 and solder 30, the latter being located on the back side of the member 25.

Each contact 29 has a flat portion and an upturned end 31, and a rearwardly inclined portion 32. These contacts are designed to cooperate with a pair of fixed contacts 33, which are secured to the base 6 by screws 34, or other suitable means. Each of these contacts has a depending portion 35 which engages the moving contacts 31.

of this kind it is important of the contacts be kept smooth and bright so 'as to establish good electrical connection. To do this the inclined'portions 31 of the contacts are arranged to slide or wipe on the stationary contacts 35. This is accomplished by making the contacts 29 flexible, and also by so arranging the member 25 that when the parts 31 and 35 contact, the member 25 will move bodily in the direction of its length a short distance away from the seat 18, as best shown This is permitted by the particular mounting of the part 25, and the coil spring 24.

By reason of the overhanging portions 15 of the frame, the contact carrying member can be readily slipped into place and be- In a switch ances, the frame acts as a means to prevent the contact carrying member from shifting sidewise, and thus insures proper contact between the stationary and, moving parts. The fact that the contact carrying-member can be threaded over the frame meansthat the. assembly operation is a simple one. By making the contacts 29 separate from the member 25, they can be made of the material best suited for the work at a very small expense. By mounting them so that they extend substantially at right angles to the plane of the member, they will in engaging the, fixed contacts 35 do so with a wiping action. Due to the fact that the member 25 can move bodily in the direction of its length against the action of the spring 24, it follows that any inaccuracy in the positions of either the moving or stationary contacts is automatically compensated for. Thisfreedom of movement of the member 25 is particularly useful to equalize the pressures exerted by insulating base having a supporting surface,

a U-shaped metal frame mounted thereon, said frame having overhanging arms at its upper end and seats below the arms, a contact carrying member having a large central open-- ing within which the lower portion of the frame is located, said member having internal shoulders which form a pivot and engage the seats, flexible contacts secured to the lower edge of the member and extending substantially at right angles thereto, stationary contacts carried by the base which are engaged by the moving contacts as they move upwardly, a swinging actuator pivotall-y supported by said arms which has a single downwardly projecting element, and a spring connecting the upper end of the'memberwith the lower end of the element, said spring causing the member and its contacts to move with a snap action and permitting the memberto rise from its bearing seats to permit of a wiping action. of the moving and stationary contacts when the circuit is closed. 3

2. In a snap switch,the combination of an rest on said surface, said frame having overhanging arms at its upper end and seatsdirectly below the arms, a sheet metal member having shoulders which rest on said seats, flexible contacts secured to the lower end of the member which have u -turned ends, fixed contacts carried by the ase having downwardly turned ends which are engaged by the flexible contacts on their upward movements, anactuator comprising a metal-head having a single downwardly extending curved element that terminates in a hook, said hook in its to-and-fro movements being arranged to strike the feet of the frame and act as a stop, an insulated cover for the head which is located between said overhanging arms and is guided in its movements thereby, a pivot for the actuator which passes through the. head and is supported by said arms, and a spring for moving said member with a snap action which is connected at one end to the member and at the other end to said hook.

3. In a snap switch, the combination of an insulating base, a U-shaped pressed metal frame, the base of which is mounted on the insulating base, said frame having a pair of overhanging arms at its upper end, a seat below each arm formed at the apex of. two diverging walls, said walls acting-as stopsfor a movable member, a sheet metal movable member having top, bottom, and side walls and a central opening within which a part of frame is located, internal shoulders formed on the inner edges of said side walls which rest on the seats, spaced contacts secured to the lower end of the member which have upturned flexible ends, fixed contacts having down-turned ends for engagement with the moving contacts, an actuator comprising a pivoted head and a single depending curved element, the end of which is arranged to engage the base of the frame and act as a stop, and a spring which connects the curved element to said movable member for actuating the latter.

In witness whereof, I have hereunto set my hand this 29th day of August, 1930.

PERCY G. SHAW. 

